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Old 12-03-2012, 01:23 PM
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I'll weigh in here with some thoughts....

A 400 motor will be fine on the drag strip without steam holes being drilled in the heads. On the street, where the motor will be run south of 3,000 rpm's and idle for periods of time, it is likely to create hot spots and spit out the head gasket. Above 2,500/3,000 rpm's, there is enough turbulence created in the water jackets that steam pockets cannot form.

Hopefully, understanding the rules and using a modicum of common sense will allow a racer to pass tech with a front-mounted fuel cell. The idea is to get it inside body lines on a doorslammer and hopefully behind a chassis crossmember. Altereds and diggers need further protection. Here's the rule.....

"Tanks: When permitted by class regulations, fuel tanks located outside
body and/or frame must be enclosed in a steel tube frame constructed
of minimum 1 1/4-inch O.D. x .058 chromoly or .118 mild steel tubing.
All fuel tanks must be isolated from the driver’s compartment by a
firewall, completely sealed to prevent any fuel from entering the driver’s
compartment. All fuel tanks must have a pressure cap and be vented
outside of body. A positive-locking screw-on fuel tank cap is mandatory
on all open-bodied cars. Insulated fuel tanks prohibited. When used,
fuel cells must have a metal box protecting the part of the fuel cell that
is outside of body lines or trunk floor, excluding hose connection area
in rear. The metal box must be constructed of minimum .024 steel or
.032 aluminum. Nonmetallic fuel cells or tanks must be grounded to

This last part of the rule probably makes no sense to some of you who have not run cells, like how do you ground plastic, but what it refers to is grounding the metal ring at the fill hole of the cell. Use a piece of 10 ga wire and crimp connectors. Any frame crossmember that is forward of the cell will work in place of the tubing protection called for in the rule, even on an open car. Take a look at any digger. All Funny Cars have front-mounted cells too. We used to be tough on firewalls. Find a very dark place, position yourself so that you can see the firewall from inside the car and have a buddy shine a very strong light on the firewall from the engine compartment. Everywhere light can shine through is a place where fuel could pass through to the driver's compartment. If that fuel was on fire, well, you get the idea. Small holes can be filled by using a fender washer on each side of the firewall with a bolt and locking nut through the middle of the washers. Larger holes will need to be welded up with patches.

Whenever the question of rod length comes up, I always refer to the articles published by Ron Iskenderian, son of the famous camfather, Ed Iskenderian......
Please read Tech Tip 2005 here....
ISKY Racing Cams - Do It Right. Race with the Legend. Camshafts, Connecting Rods, Valve Springs, Lifters

Last edited by techinspector1; 12-03-2012 at 01:34 PM.
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